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Its interesting to see the way that, 5 minutes after learning the word "optogenetics" (at least in my case), we already see factions of staunchly pro and anti opto-genetic slashdotters forming the battle lines.

Im willing to bet that some of these articles are made up of whole cloth by the editors, just to see how many people will argue for and against the made-up topics.

Nah nah nah, Bob,D.C. just jump on every thing with science to spill his garbage about subluxation and the benefit of chiropractic and how he can fix every disease and trouble of the human being from autism to cancer and probably the world hunger too.

A retrovirus is made to "attack" the DNA of a cell. A neuron is not made for that, it can't inject new DNA to other cells.

Plus, a neuron don't divide as other cells do. Well, it happen for specific type of neuron, but it mostly stem cells. So most of them don't divide, and if they do, they will divide as the same cell, with the same DNA markers.

You should try real science, instead of trying to scares people with random Hollywood scenarios.

Optogenetics have been around for a few years and have proved to work splendidly in mice. Now of course in mice the usual approach is to drill a hole in the skull and feed a fiber optic cable into it, for a human you would probably miniaturize some light emitting device and embedd it inside the skull.

The reason why optogenetics is so much better than electrodes is not only for the fact that you require physical electrode present to act as a growth area for scar tissue, but that you can target specific ne

Yeah, They go through a ton of mice. Mice breed like... well, mice. 3-12 offspring every month or so, starting from age 6 weeks and going for about a year. A female mouse could easily be "bedded" by her great-great-great-great-great-great-great-grandson and she could have over 35 million ancestors at that point.

They are already talking about the possibilities for therapy and behavior modification by optically stimulating specific brain circuits.

They can talk about it all they want, but until they invent a transparent skull, I'm not sure I see many practical applications.

There are conditions (Parkinson's, epilepsy, severe depression) in which people get electrodes implanted in their brains, with (sometimes) therapeutic benefits. Optical stimulation can be much more precisely targeted and controlled -- with good DNA delivery vectors, you can target specific cell types, or the neurons connecting two brain regions. Optical stimulation, I believe, also causes less cell damage than direct electrical stimulation.

Skin is actually light sensitive. Pain receptors are directly connected to neurons. It could be used for torture, if they found a way to replace regular sub-cutaneous skin neurons with photosensitive ones.

it's already done, but lower in the spectrum. 95GHz waves, or 3.2 mm ones are used in the "Pain Ray" to remotely provoke unbearable pain in an outer layer of the skin. It's sold as the way of the future to quell protests, though good old water cannon and bullets are cheaper. There's even a commercial [youtube.com] about it.

If making a reliable long-term electrical connection between neurons and circuitry continues to be as hard as it has been so far, then this technique could offer a superior way of coupling the brain to cybernetics. Neurons would only need to be near the input device, not need to be touching it. The brain would figure out what the signals meant just as easily.

So far I don't think there's optogenetic tools to read output from neurons, just input methods. Although I'm willing to put my manhood at stake that voltage-triggered-fluorescent membrane proteins exist already in some form.
As for ordinary electrodes, it is getting easier all the time.

Can't put a finger on actual voltage triggered fluorescent proteins - but you can get voltage triggered structural change in membrane proteins, and from there it is just the problem of attaching a fluorescence label that is sensitive to it's environment and you should be able to grab a signal off it. Of course, implementing that in a living brain is another problem....

Some deep-sea luminescent creatures I've seen videos of flicker their lights in surprisingly intricate patterns. Too fast for hormonal cotrol. I would guess neural. There is a nice starting point to sequence.

Well, the thing you're missing is that it is connected to the brain via the optic nerve. None of the image processing is done in the eye, it just signals the nerve which signals the brain to process. I'm not sure that simply being neurons qualifies the retinas as being part of the brain.

An alternative technique to Optogenetics is called Magnetogenetics, which in my opinion may have even more clinical relevance. In optogenetics, viral vectors are used to transfect the opsin of choice in the neuronal population of choice, and then those neurons can be stimulated by the wavelength of light specific to that opsin. The newer and less well known technique of Magnetogenetics, uses viral vectors to transfect a specific ion channel that opens in response to magnetic stimulation of a certain frequ

Hah, I recall a story my NMR prof told in one of his lectures. Back in the 50s, when biomolecular NMR just started out, the theory that memory was based on magnetic fields had been floating around. One of the early masters of NMR thought it was bullshit, and proceeded to stick his head into a magnet assembly producing a field of a couple of Tesla, just to prove his point. Fortunately for him, he proved to be right.

That might be blowing the effectiveness of the tool out of proportion a bit. For one thing, "memory" is spread over numerous regions of the brain, among hundreds of different neuronal and non-neuronal cell types. Simply affecting one type via magnetogenetics would likely not have too much of an impact on something this complex. However, stimulating dopamine neurons in the substantia nigra of a parkinsons patient using a tool such as this would theoretically restore motor function similarly to deep brain

I don't have the paper at hand, but I recall reading about optically activated neurons being created in a mouse model years ago. Leave a hole in the skull, connect with fibre optics and activate at will. I'd have to dig through my files to find the proper citation, though - so I might be mistaken, but this sounds awfully familiar.

The summary is a bit remiss in not mentioning Karl Deisseroth's group at Stanford, who have really made this technique practical. I'm at a different (also good) neuroscience lab, and his group's work looks like magic to me -- they've crossed a lot of t's and dotted a lot of i's. It's really, really elegant, and has a lot of therapeutic potential in humans.

I've been lucky enough to see Deisseroth speak a couple of times (always in a packed auditorium). The pace at which he displays his results and the value of the results themselves is almost mind-boggling. He'll talk about a really great result they got with an experiment inhibiting fear in mice (if I recall, they targeted the amygdala and then showed the animal hiding in corners of the cage until they turn on the laser and he runs across the open space) and then before you can wrap your brain around it he's already moved on to talking about revolutionizing Parkinson's research by selectively inhibiting dopaminergic neurons.

As if inventing a groundbreaking technique and using it to solve all kinds of interesting problems isn't enough, Deisseroth has also been very proactive about sharing his techniques and methods, to the point that his lab actually holds workshops for other neuroscientists to learn how to do similar work. A pretty awesome guy all around, and I suspect he'll be the recipient of a Nobel Prize before too long.

They've made a great video showing optical control of a mouse's motor cortex,

OK IAAS (I Am A Scientist) and I can appreciate the potential for good with this research but watching that video... it's just a little creepy to see a living animal quite literally turned into a robot. Maybe it's just watching too many episodes of STNG. OTOH I bet there are (some) military and covert agency types who got a hardon watching it.

Using viruses (see TFA) to implant the necessary genetic changes to motor neurons, prisoners and other bad people can be 'prepared' for control by authorities... but then so could we all, without our knowledge or consent... even at birth.

What is really chilling is the sense that the articles author sees nothing wrong with controlling a brain. Of course it would be hard for him to see past his ego.